This invention relates to a battery device having a chargeable secondary cell or a primary cell such as a dry cell in its housing member, and an electronic equipment such as a video camera or a video tape recorder employing the battery device as a power source.
In a portable electronic device, such as a video camera, video tape recorder, tape player or a disc player, a dc power source such as a rechargeable battery or a dry cell is adapted to be used in addition to a commercial power source supplied via a dc adapter.
With the battery, a battery loading unit is mounted at a portion of a main body of the device, and a battery housing a rechargeable cell or a dry cell is loaded on the battery loading unit. The battery having the rechargeable cell enclosed therein is loaded on a charger having a dc adapter for charging.
The battery pack employed in an electronic device such as a video camera or a video tape recorder has a housing unit for housing plural batteries in order to procure a voltage sufficient to drive the electronic device or a capacity sufficient to drive the electronic device for longer than a preset time period. This type of the battery device has a housing unit having two rechargeable cells arrayed side-by-side therein.
The battery pack 2, having two cylindrically-shaped rechargeable cells 1, 1, has a housing unit 4 having a cell housing section 3 having a size sufficient to hold two rechargeable cells 1, 1, side-by-side therein, as shown in FIG. 26. The housing unit 4 is molded of synthetic resin and is adapted to hold cells 1, 1 arranged side-by-side in the cell housing unit 3 in a hermetically sealed condition, as shown in FIG. 27. The two cells 1, 1, housed within the housing unit 4, are connected in series with each other via an electrode plate, not shown, in the cell housing unit 3.
The bottom side of the housing unit 4, housing the two cells 1 side-by-side in the cell housing unit 3, is integrally formed with a terminal connecting plate 7 having embedded therein a positive terminal plate 5 and a negative terminal plate 6 electrically connected to a connection terminal of an electronic device on which is loaded the battery pack 2, and having a connection line, not shown, electrically connecting the positive and negative terminals 5 and 6 to the electrode plate 7. The positive terminal 5 and the negative terminal 6, provided on the terminal mounting plate 7, are adapted to be electrically connected to a pin-shaped connection terminal provided on the electronic device on which the battery pack 2 is loaded. The tubular-shaped positive and negative terminals 5, 6 are mounted on both sides of the terminal mounting plate 7 for facing an end face 8 which is the loading side of the battery pack 2 into the electronic device, as shown in FIG. 28.
The tubular-shaped positive and negative terminals 5 and 6 are mounted at both ends of the terminal mounting plate 7 with opening ends 5a, 6a thereof facing the end face of the battery device 2 along the loading direction of the electronic device.
The above-described battery pack 2 is substantially rectangular in shape conforming to the outer shape of the two cells 1, 1 arranged side-by-side. Both sides of an upper surface 9 of the housing unit 4 are formed as arcuate portions 10, 10 conforming to the outer peripheral surface of the cells 1, 1. The battery pack 2 thus formed with the arcuate portions 10, 10 on its upper surface is vertically non-symmetrical in shape so that its vertical orientation can be discerned easily.
The above-described battery pack 2 may be loaded so as to be housed within a battery loading section 14 formed in a portion of an outer casing 13 of a video camera 12, as shown in FIG. 29. That is, the battery hosing unit 14 having a size sufficient to hold the battery pack 2 in its entirety is formed as part of of an outer casing 13. The battery loading section 14 is formed by partitioning a portion of the outer casing 13 and has a pair of connecting pins 17, 18 on its inner wall surface facing an opening 15 for the insertion or removal of the battery pack 14. The connecting pins 17, 18 are adapted to be respectively connected to the positive terminal 5 and the negative terminal 8 provided on the battery pack 2.
The battery pack 2 is loaded in the battery loading section 14 by being inserted in a direction shown by arrow A in FIG. 29 via an opening 15, with the end face 8 on which the opening ends 5a 6a of the positive terminal 5 and the negative terminal 6 are opened. At this time, the positive terminal 5 and the negative terminal 6 are connected to the connecting pins 17, 18 and the battery pack 2 is electrically connected to the video camera 12 so that the power of the cells 1, i may be fed to the video camera 12.
The housing unit 4 of the battery pack 2 has a groove 11 in its upper surface 9 for ensuring that the battery pack 2 is inserted into the battery loading section 14, as shown with the proper orientation in FIGS. 26 and 27. The groove 11 is open at 11a in the inserting side end face 8 of the battery pack 2 and is formed parallel to the loading direction with respect to the battery loading section 14. On the inner lateral surface of the battery loading section 14 is formed a rib 19 for extending from the opening 15 as far as its mid portion so as to be engaged in the groove 11. By providing the groove 11 in the battery pack 2 and by providing the rib 19 which engages the groove 11 in the battery loading section 14, the battery pack 2 can be loaded in the battery loading section 14 only when the battery pack is loaded with the rib 19 in proper registration with the groove 11, thus inhibiting mistaken insertion of the battery device into the battery loading section 14.
There is also proposed a second battery pack 22 having a housing unit 4 further housing a second row of two series connected cells 1 and thus housing four cells 1, as shown in FIG. 30. With the second battery pack 22, the first row of two juxtaposed cells 1, 1 stacked on the second row of two juxtaposed cells 1, 1, are housed in their entirety in the housing unit 24, as shown in FIG. 31. With the second battery pack 22 having the two by two cells arranged side-by-side in the housing unit 4 the construction of the terminal mounting plate 7 is the same as the first battery pack 2 housing the two cells 1, 1, in which the positive terminal 5 and the negative terminal 6 are embedded in the terminal mounting plate 7 and connected to the connecting pins 17, 18 provided on the video camera 12. Since the second battery pack 22 shown in FIGS. 30 and 31 has a first row of two juxtaposed cells 1, 1 stacked on a second row of two juxtaposed cells 1, 1, the second battery device differs from the first battery 2 only with respect to height H.sub.1. The width W.sub.1 is the same as the first battery pack 2, with the two battery packs being substantially similar in shape to each other. Since the two battery packs are substantially similar in shape to each other, the groove 11 for preventing mistaken insertion into the battery loading section 14 may be of the same constitution for both the first and second battery packs 2 and 22.
In addition, since the second battery packs 22 houses within the housing unit 24 two cells 1, 1 arranged in two rows, the cell housing efficiency may be improved to reduce the size of the device 22 so that the battery loading section 14 of the electronic device on which the battery pack 22 is loaded may also be reduced in size.
Meanwhile, it is desirable that the first battery pack 2 housing two cells 1 and the second battery device 22 housing the four cells 1 be selectively loadable on a common electronic device. For example, if the video camera 12 is employed for a prolonged time or a shorter time, it is desirable to load the second battery pack 22 housing the four cells or to load the first battery pack 2 housing two cells, respectively.
For such selective loading of the first battery pack 2 housing the two cells 1 or the second battery pack 2 housing the four cells 1, it is necessary to design the battery loading section 14 having a size sufficient to hold the large-sized second battery pack 22 in its entirety, as shown in FIG. 32.
The second battery pack 22 houses the two side-by-side cells stacked on two other side-by-side cells, with the four cells being cylindrical in shape and of the same size and with an end face 28 thereof being substantially square, as shown in FIG. 31. Thus a diagonal line S.sub.1 of the end face 28 is substantially equal to a width W.sub.1 of the first battery pack 2. Thus, in or attempted to load a battery loading section 25 capable of loading the large-sized second battery pack 22 with the small-sized first battery pack 2, the first battery pack 2 can be loaded not only in the normal loading position in which it is inserted with the terminal mounting plate 7 in contact with the bottom surface 25a of the battery loading section 25 and with the positive terminal 5 and the negative terminal 6 being connected to the connection pins 17, 18 within the battery loading section 25, but also incorrectly in an inclined position along the diagonal direction of the battery loading section 25, as shown with a chain-dotted line and double-dotted chain line in FIG. 33. In addition, the first battery pack 2 can be loaded with its upper surface 9 extending along the upper surface 25b of the battery loading section 25, as indicated by a broken line in FIG. 33. If the first battery pack 2 is loaded with a tilt relative to the battery loading section Z5 or with an offset towards the upper surface 25b, the positive and negative terminals 5, 6 cannot be connected to the connecting pins 17, 18 of the battery loading section 25, as a result of which the first battery pack 2 is incorrectly loaded and electrical connection cannot be established with the video camera.
On the other hand, since the cells in the battery pack are heavier than the components making up the electrical device, the battery pack housing the cells is relatively heavy. The battery pack having plural cells housed within a housing unit is increased in weight depending on the number of the cells housed therein. It thus becomes important to load the battery pack housing plural cells and having an increased weight on the battery loading section with correct positioning and orientation. If the battery pack having a large weight is loaded in the battery loading section without correct positioning and oscillates in the electronic device in which it is loaded, a large impact may be applied to the electronic device in which the battery pack is loaded, thus causing the risk that the electronic device is occasionally damaged. Above all, the connection terminals interconnecting the battery pack and the electronic device may be easily damaged by such impact.